Pandolfini's Puzzler #35 - The Good Knight

Professor: Good day, class. Would you rather be a knight? Or would you rather be a bishop?

Zephyr: That’s quite a “hello,” Professor.

Lucian: I’m fine. How are you?

Professor: I’m doing OK. Forgive me for getting right into matters. It’s a trait I’ve picked up earlier today.

Lucian: If you’re asking whether I prefer having a bishop or a knight, most of the time I would say a bishop.

Zephyr: But certainly not all the time. True, in many positions, I’d prefer having a bishop. But sometimes I’d rather have a knight.

Professor: In general, when would you feel better off with a bishop, and when would you rather have a knight?

Lucian: It’s not always so easy to say. If the position is open, and possible attacks can emerge on both sides of the board, I’d probably rather have a bishop a lot of the time. But, as Zephyr suggests, I wouldn’t want to have a bishop all the time, automatically.

Professor: That sounds reasonable. And when would you rather have a knight?

Lucian: If the position is blocked up, knights may be able to outmaneuver bishops, since they can jump over obstructions. In many of those cases, where pawns mess up and close off lines, I’d rather have a knight.

Zephyr: Still, even when the situation is blocked up, as Lucian implies with his careful language, sometimes a bishop could be better anyway.

Professor: You mean that it really does depend on the actual specifics of the position in front of you?

Zephyr: That’s right, Professor. You’ve often demonstrated in this class how ineffectual general principles can be if we follow them too rigidly or rely on them too much.

Professor: What about when it comes to trapping other pieces? Do you have any thoughts on those possible circumstances? Do you think one type of minor piece is typically better than the other?

Lucian: It does seem that a bishop can on occasion trap a knight.

Zephyr: Yeah. I think you call it corralling a knight.

Professor: Right again. Just so that we’re on the right page, take a look at this ridiculously simple position. It exemplifies the concept.

Question 1: How can White win the knight?

Lucian: That’s so easy, Professor.

Zephyr: But it does display what you’re getting at, that bishops can sometimes corral knights.

Professor: Does that mean that knights can’t trap bishops?

Lucian: No, not at all, Professor.

Zephyr: There are plenty of occasions where blocked-up bishops can run into knight trouble.

Professor: Oh, not only in blocked-up positions. Even on a wide open board, there are instances when a knight can run fences around a bishop. The trick characteristically depends on a knight fork. Consider the position of diagram 2.

Question 2: How can White win the bishop?

Lucian: I got it!

Zephyr: I have it also.

Professor: Eureka! Now you’re reasoning like Archimedes. Let’s see if you can continue to think as sharply as he did in our next problem. But watch out for any wild Roman soldiers with swords.

Question 3: Can White win the bishop?

Lucian: I think I see how White can win the bishop.

Zephyr: Me too. Although White might have to step carefully to bring home the point.

Professor: I’m glad you see the point about bringing home the point. But before we fail to go any further, let me point out that we’re about to see another problem.

Zephyr: Thanks for pointing us in the right direction.

Lucian: And you did it so pointedly!

Question 4: Can White win the bishop?

Zephyr: Professor, these positions are very similar.

Lucian: Yeah, they exhibit similitude.

Whatever the positions exhibited, the excelling students had gotten all the correct answers so far. You could almost feel that they wanted a problem or two more.

Professor: You know, I think this calls for another problem.

Zephyr and Lucian: We were hoping you’d say that, Professor.

Question 5: Can White win the bishop?

Zephyr: That’s still the same idea, with a slight difference. But, miniscule differences or not, I must say, these problems are fun.

Professor: You mean you’ve figured it out already?

Zephyr: Pretty much.

Lucian: It’s really the same kind of inspiration after all.

Naturally, the two heurists found the way to win the bishop. It took 2.5 minutes. Somebody timed it.

Professor: Does that indicate you’re willing to try another problem?

Zephyr and Lucian: Absolutely!

Professor: Fine! One more problem coming up! Let’s say we’re doing it for “the roads not taken” in our past lessons.

Zephyr: Oh, Professor, did you have to allude to Robert Frost in a chess lesson? I don’t think he played chess. But he is one of my favorite poets.

Lucian: He’s one of mine, too.

Professor: OK. Here we go. Let’s call it the Frosting on the cake.

Question 6: Can White win the bishop?

For all the above problems, can you work out all the roads that should be taken?

Answer below - Try to solve ProfessorPando's Puzzle first!

ANSWER #35

For problem 1, White wins the knight by 1. Be5! That corrals the knight, which is then gobbled up by the upcoming g2-g4.

For problem 2, White starts to win the bishop by 1. Nd6!, threatening promotion. After 1…Kxc7, the bishop falls to the forking check, 2. Nxb5+.

For problem 3, White starts to win the bishop by 1. Kg1!. Then it depends where the bishop goes.

To start with, g2, d5, and a8 are off limits for the bishop, since they are under White’s control. Then there are the so-called safe squares, f3, e4, c6, and b7.

If 1…Bf3, then 2. Ne6 Kxf7 (essentially forced) 3. Ng5+ (a forking check) wins the bishop.

If 1…Be4, then 2. Ne6 Kxf7 (essentially forced) 3. Ng5+ (a forking check) wins the bishop as well.

If 1…Bc6, then 2. Ne6 Kxf7 (essentially forced) 3. Nd8+ (a forking check) also wins the bishop.

And if 1…Bb7, then 2. Ne6 Kxf7 (essentially forced) 3. Nd8+ (a forking check) once again wins the bishop.

For problem 4, White goes after the bishop by 1. Ka2!. Now, no matter where it goes, it’s lost.

First of all, b2, e5, and h8 are off limits, being controlled by White.

Meanwhile, if 1…Bc3, then 2. Nd6+ Kxc7 3. Nb5+ (a forking check).

If 1…Bd4, then 2. Nd6+ Kxc7 3. Nb5+ (a forking check).

If 1…Bf6, then 2. Nd6+ Kxc7 3. Ne8+ (a forking check).

And if 1…Bg7, then 2. Nd6+ Kxc7 3. Ne8+ (a forking check).

For problem 5, White must begin by saving the knight, which leads to the win of the bishop after 1. Nd7!.

This placement also creates a barrier between the black king and the g-pawn, since White now guards three straight squares on the f-file: f8, f7, and f6.

If Black then tries 1…Bf4, with the idea of shifting to h6, the bishop is lost after 2. g7 Kf7 3. Nf6! Kxg7 4. Nh5+ (a forking check).

The same ending happens after 1…Bg3 2. g7 Kf7 3. Nf6! Kxg7 4. Nh5+ (a forking check).

If Black instead tries 1…Bc7, then the bishop goes after 2. g7 Kf7 3. Nf6 Kxg7 4. Nd8+ (a forking check).

If Black tries 1…Bd6, the bishop falls similarly to 2. g7 Kf7 3. Nf6 Kxg7 4. Nd8+ (a forking check).

And if Black moves his king, say 1…Ke6, then 2. Kg2 forces the bishop to move to one of the bad squares already considered.

For problem 6, we see the knight is immune to capture because the h-pawn will then queen.

White has constructed a small barrier (g7 and g6), so that Black’s king can’t immediately approach the h-pawn.

Meanwhile, the black bishop can’t safely go to d4 and f2 because White guards those squares, and moving the bishop to b6, b8, c5, or e3 loses it to forking knight checks.

That leaves only one safe bishop move for Black, to g1. Accordingly, Black is up the creek after 1. Kf1!. Unless Black is willing to let the h-pawn queen, the bishop is soon lost.

Take note

If you want to follow up on more of these concepts, the above forking ideas, where knights get the better of bishops, are especially illustrated in some of the problems of two great composers: Richard Reti (1889-1929) and Alexey Troitzky (1866-1942). And if you’d like to experience great chess art beautifully organized and presented, there is no better book on compositions than “Domination in 2,545 Endgame Studies” by Genrikh Kasparyan. It’s a true treasure.